 DISCUSSION: The intense heat generated by wildfires causes air to rise. To replace the rising air at the surface, air must converge. Sometimes as it converges, it begins to rotate. Similar to an ice skater pulling in her arms, as this rotation gets squeezed smaller, it speeds up. Nevertheless, most rotation generated by fires (called fire whirls by the National Weather Service) is relatively weak and/or occurs far from populated centers such that they don't cause much additional damage already generated by the fire itself. Such was not the case for a fire whirl generated by the Carr Fire in California on July 26, 2018 (pictured above). This particular whirl (dubbed a "fire tornado" by the California Department of Forestry and Fire Protection) had wind speeds of up to 165 mph, equivalent to an EF-3 tornado, that destroyed homes, trees, and transmission towers. In addition, two fatalities were attributed to this fire whirl. It also lasted a lot longer than typical fire whirls of ~80 minutes.
There were a lot of pictures, videos, and data collected near this fire whirl that scientists are now combing through to try to better understand the conditions that spawned this intense whirl and perhaps better predict their occurrence in the future. However, small, transient circulations in the atmosphere are very difficult to predict when only atmospheric dynamics are at play. But, here there is an interplay between atmospheric and fire dynamics, making understanding this fire whirl even more challenging. In addition, documentation of fire whirls this intense are rare, further complicating our understanding of these events. What scientists do know is that while damage caused by this whirl is comparable to a tornado, the conditions and forces that generated it are far different that those governing the more typical formation of tornadoes from supercell thunderstorms. Hence, the National Weather Service is hesitant to call this event a "fire tornado." In addition, we cannot say this event was caused by climate change. Climate change occurs on a much larger space and time scale than this fire whirl. In addition, it is possible that these types of events occur more often in rural areas where they are more difficult to observe, and there is less to damage, thus inhibiting an accurate estimation of intensity. Nevertheless, there is still much to be learned about fire whirls, in particular these high-intensity ones. To learn more about fire weather and fire weather education, be sure to click here! © 2018 Meteorologist Dr. Ken Leppert II
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 DailyFly  As the summer season comes to an end, it is important to note the many extreme weather events that have been and still are occurring worldwide. Wildfires have ravaged the American West and much of Europe; heavy rainfall caused extreme flooding on the US East Coast; a hurricane barreled towards Hawaii; and extreme heat caused deaths in large metropolitan areas such as Montreal and Tokyo. While none of the aforementioned events can be attributed to any specific cause, it’s important to note the role climate change may have had in the frequency of these events and draw attention to what is speeding up the process of climate change.
One of the biggest factors in climate change does happen to be carbon emissions. It is thought that the emission of carbon dioxide and other greenhouse gases offsets normal climatic processes by blocking incoming solar radiation, thereby having an indirect influence on extreme weather events. After a plethora of extreme weather events worldwide this summer, the state of Washington has decided to add a carbon tax to this November’s ballot. If passed, the state would be the first in the nation to establish such a tax via voters. The plan has come to be known as Ballot Initiative 1631, and with the tax set at $15 for every ton of carbon dioxide released, it’s expected to generate over $2 billion in the first five years. The tax will tax some of Washington’s largest industrial polluters. Revenue will go towards the production of energy efficient fuels, such as wind and solar, and related industries throughout the state. The project also plans for the mandatory allocation of one-quarter of its funds to protecting the state’s forests. A smaller portion of the revenue will go towards transitioning communities away from economic dependence on fossil fuels and protecting the most vulnerable communities in the state from climate change. While there seems to be some consensus pointing to a mostly positive outcome of the tax, a relatively prevalent opposition movement threatens the passage of the initiative. Dana Bieber told The Atlantic “regardless of what you say about a carbon fee or a carbon tax, it’s intended to be paid by consumers”. Bieber was referring to the notion that the state’s largest polluters will suffer economically. The price tag would eventually trickle down to consumers, says the non-partisan think tank Resources for the Future, adding over 10 cents a gallon to the price of gas and 15 cents a gallon to the price of home-heating oil. Initiative supporters, backed by the state’s government, say that the policy would cost residents at most $10 a month with much of the money being granted back to communities vulnerable to climate change and in economic despair. Whatever the outcome of the November election, it is important to note how the current weather in Washington may play a role in the election. Wildfires, some of which have been burning since late July, have plagued many rural and forested areas statewide. Several media outlets, such as the Yakima Herald and Heavy.com, allow users to track the status of fires with digital maps displaying the locations of the fires and individual statistics. It was reported on August 12th that fires in Washington and Oregon combined burned over 250,000 acres, prompting an elevated risk of wildfire weather early in the season and into the Fall, when wildfire season peaks. While the wildfires have burned in mostly forested parts of the state, a huge bulk of the population has felt the effects of the storm, possibly influencing Initiative 1631’s chance of passage. Seattle has reported extremely low air quality, according to a Daily Mail interview with Seattle residents, with some Seattleites going as far as noting Beijing’s infamous air quality as being better. Prevailing weather patterns on the windward side of the Cascades have heavily influenced Seattle’s summer haze. Unless Seattle’s rainy season arrives earlier than the average late Fall/Winter peak, the city’s residents could be in for a long stretch of diminished air quality and hazy conditions. It’s safe to say when Ballot Initiative 1631 is up for election this November, voters in Washington will be keeping in mind the physical, topographical and climatic status of their state. Want to learn more about wildfires? Check here! © 2018 Weather Forecaster Jacob Dolinger  The Carr fire is now the second most expensive wildfire with an estimated $25.4 million is suppression costs. This estimate does not include costs associated with damage from the fires. The death toll of the Carr fire has risen to six. The fire that has ravaged over 110,000 acres and continues to burn has prompted the action of over 3,600 fire personnel. With over 500 structures already impacted, the California Department of Forestry and Fire Protection say nearly 5,000 more are in immediate threat from the fires. As in most cases the current and future weather conditions are aiding in the future spread and limited containment of the fire. The combination of high winds, high temperatures, and dry vegetation has aided in conditions that are prime for fire growth. The Carr fire has been burning since the beginning of last week. It was likely started by a car that suffered mechanical failure. One positive note is that the containment is up from 5% to nearly 27% as of early this morning.
The National Weather Service (NWS) in Sacramento predicts very hot and dry surface conditions are in concert to create an environment that will allow this fire to continue spreading even with light winds. Relative humidity values less than 15 percent and maximum temperatures in the middle 90’s are expected across the area. The highest threats are near the city of Redding and surrounding areas where irregular spreading of the fire is possible. It is also important to remember that fire behavior is difficult to predict, and wildfires can generate their own micro scale wind circulations and produce higher winds near the fire itself that are different from synoptic winds. To learn more about fire weather and fire weather education, be sure to click here! © 2018 Meteorologist Allan Diegan  Discussion: Dangerous wildfires have been burning through multiple states in the West over the past month. These wildfires have burned over one million acres of land across fourteen states according to the National Interagency Fire Center. The hot temperatures and the dry weather that the western parts of the United States have endured have been one of the primary catalysts for these wildfires breaking out. These weather conditions have given firefighters a hard time with containing these wildfires due to the dry vegetation and blowing winds allowing for erratic fire behavior.
In California, there are currently 5 active wildfires that are burning. The largest of these is the Carr Fire in Shasta County north of Redding, CA, which has burned 98, 724 acres, and is twenty percent contained. The River Fire and Ranch fires in Mendocino County, CA are both wildland fires and have burned 35,076 acres and 20,911 acres respectively in that area. The fires in Mendocino County are five percent contained. The Ferguson fire is a vegetation fire near Yosemite National Park that has burned 54,481 acres and is thirty percent contained. Parts of Yosemite National Park were closed as a result of the fire. The Whaleback fire in Lassen National Forest has burned 14,098 acres and is twenty percent contained. All of these wildfires have prompted mandatory evacuations across many parts of the state. Other states are battling wildfires as well. Multiple states across the western United States are currently battling one or more fires. Four states Alaska, Oregon, Colorado, and Arizona are battling ten or more wildfires. In total ninety fires have occurred in the month alone. According to the National Interagency Fire Center, this is an unusually high amount of fires for July. With the advancements in satellite technology, meteorologists are able to detect where the smoke from these fires is traveling. Using the GOES-16 satellite, meteorologists can see what locations the smoke from the fires is being carried to. Using the shortwave infrared channel on the GOES-16 satellite meteorologists can pick up hot and small fires. During the daytime, the visible channel can aid in fire detection by picking up on wind changes and also see hotspots from the fires flaring up in different parts of the state. Wildfires are not just a danger on the ground. The smoke from the wildfires currently burning is affecting the air quality across the western region. Poor air quality is dangerous for many sensitive groups like the elderly, young children and those with compromised immune systems. If you are apart of one of the sensitive groups it is vital to limit your exposure to wildfire smoke. It is also important to take steps to protect yourself from the fires and the smoke and to follow the safety orders and evacuations issued by the authorities. It is also important in these weather conditions to exercise caution when using items that could ignite a fire i.e. cigarettes, campfires, and brush clearing equipment, as any small fire could spread rapidly. To learn more about fire weather and fire weather education, be sure to click here! © 2018 Meteorologist Shannon Scully  In recent weeks, California firefighters are continuing to struggle with containing a blaze that is ripping apart nearly 9,300 acres of land near Yosemite National Park in the Sierra Nevada Mountains. While this is a frightening event, unfortunately it’s a normal occurrence and harsh reality for many people living in the western part of the United States. Many people may feel powerless and unsure of how they can help. It is crucial to know what causes these wildfires and how citizens can protect themselves, their families, as well as their property.
The biggest initiator of wildfires is due to human activity. It has been stated by the National Park Service that as many as ninety percent of wildfires are caused by campfires being left unattended, the burning of debris or leaves, negligently discarded cigarettes, and intentional acts of arson. Fortunately, in some states, legislation has been passed to prohibit acts of burning leaves on property, as well as the time of year of doing so. In Massachusetts, for example, the timeframe of burning leaves is from January 1st to May 1st and only from 10:00 AM and 4:00 PM. It also must be at least 75 feet from buildings. However, even though this law is enacted, there are still twenty-two areas in Massachusetts that prohibit the act of burning leaves completely. Another cause of wildfires is due to lightning. Lightning is described as having two components - dart leaders and return strokes. The leader is the build-up of positive charges on the ground beneath the cloud, attracted to the negative charge in the bottom of the clouds. The return streaks of light are a series of strokes that produce the actual lightning bolt or flash that we see. There are two types of lightning which are described as “cold lightning” and “hot lightning”. Cold lightning is a return stroke with intense electrical current but of relatively short duration. Hot lightning has currents with less voltage, but these occur for a longer period of time. Fires are usually started by unusually long-lasting hot lightning bolts. Wind is also impactful on creating wildfires. For example, in California there is a phenomenon known as the Santa Ana winds. These winds are strong, extremely dry down-slope winds that originate inland and affect coastal Southern California and northern Baja California. They originate from cool, dry high-pressure air masses in the Great Basin. Santa Ana winds are known for the hot, dry weather that they bring in autumn but can also arise at other times of the year. They often bring the lowest relative humidity of the year to coastal Southern California. This low humidity, combined with the warm, heated air mass, plus high wind speeds, create critical fire weather conditions. Also known as "devil winds", the Santa Anas are infamous for fanning regional wildfires. Homeowners in wildfire prone areas should keep all of this information in mind, as well as taking their steps to prevent the spreading of these fires. First off, homeowners should remove combustibles including firewood, yard waste, barbecue grills, and fuel cans from their property. Before evacuating, close all windows, vents, and doors to prevent a draft. Shut off natural gas, propane, or fuel oil supplies as well as filling any large containers (such as pools, hot tubs, garbage cans, or tubs) with water to slow or discourage fire. Homeowners should heave warning from local first responders, police and/or firemen for when to evacuate. You should never stay and try to put out the flames yourself, as the flames can engulf properties in mere minutes. While fire season is a scary event for anybody - people that live in wildfire prone areas should be knowledgeable on what to do, try to remain calm if they are asked to evacuate as well as to be safe at all times. To learn more about other global climate stories and/or topics, be sure to click here! For more information on fire weather, click here! ©2018 Weather Forecaster Michael Ames  DISCUSSION: On June 1, 2018, a fire was started in the San Juan National Forest in southwest Colorado about 100 miles from the Four Corners, the intersection of Colorado, Arizona, New Mexico and Utah. The fire which is named the “416 Fire” is approaching the end of its third week of burning with about 37% containment and has burnt over 35,000 acres in the San Juan National Forest. The fire has also sparked a second fire called the “Burro Fire” about 5 to 10 miles to the west which has burnt over 3,000 acres with 53% containment. The cause of the 416 Fire has not been determined although it started on the railroad tracks in the National Forest.
Weather conditions have been favoring the spread of the fire since the onset. Afternoon temperatures have predominantly hovered from the mid-80s to the low-90s throughout much of the fire with humidity down into the single digits during the day and only up to 50% during the overnight hours. In addition, there has been a dominant westerly and southwesterly wind especially in the afternoon hours. This flow is bringing dry air uphill which helps spread the fire with a wind shift at night to a northerly wind. However, there was a small upper level trough that brought moisture to the area on the 16th and 17th of June which brought about 0.80 inches of rain to the fire zone but helped reduce the fire within its footprint. The National Weather Service is forecasting for more temperatures in the upper 80s throughout the week with continuing low humidity, westerly winds and a slight chance of thunderstorms which would unfortunately help fuel the fire. The fire has led to a temporary two-week closure of a stretch of US Highway 550 which is near where the 416 Fire originated. In addition, the fire has led to the suspension of all services of the Durango and Silverton Narrow Gauge railroads which run through the forest. The nearby city of Durango shut down hiking trails due to the concern that the fire would spread there. Evacuations have been ordered for many of the nearby small communities, however, many residents have been allowed to return due to the rain on the 16th and 17th. Also, Durango officially reopened their trails on June 21st. No damage to homes or deaths from the fire have been reported. To learn more about fire weather and fire weather education, be sure to click here! © 2018 Meteorologist JP Kalb  It has been a dry start to the spring season in the southwestern United States. The above-average temperatures and lack of rain has caused dry ground conditions and significant drought. The National Weather Service has issued Red Flag Warnings for parts of the desert southwest. Above-normal temperatures combined with the lack of moisture has created critical fire weather conditions that remain in place due to gusty sustained winds up to 30mph combined with low humidity values in the single digits.
The ongoing drought in the area is another risk factor to this start of the spring. According to the U.S. Drought monitor, made by the National Drought Mitigation Center, there are four levels of drought ranging from D0 (abnormally dry) to D4 (exceptional drought). Drought conditions are present across a majority of areas in the desert southwest but levels of D3 drought, which is extreme drought and D4 exceptional drought levels, are most prevalent in parts of the four corners region of the United States. For parts of southern and central plain states, red flag warnings are also in effect there. Parts of central Minnesota and northern Iowa have had gusty wind conditions 20-25mph, relative humidity values dropping into the twenties and afternoon high temperatures in the high 70s and low to mid-80s. These conditions are likely to remain throughout the afternoon and evening. During a red flag warning, it is extremely important to heed local burn bans, properly discard any cigarettes, and avoid activities that cause open flames or sparks. With the dry vegetation, warm temperatures, gusty winds, and low humidity it doesn’t take much to spark a brush fire or even a wildfire! To learn more about fire weather and fire weather education, be sure to click here! © 2018 Meteorologist Shannon Scully Red Flag Warnings in Effect for Parts of Southern California! (Credit: NWS Los Angeles/Oxnard)1/28/2018  Discussion: Red Flag Warnings are in effect for parts of Southern California as fire weather conditions reach critical levels throughout the weekend into Monday afternoon. A moderate to locally strong Santa Ana wind event has developed over the area. These winds combined with the near record temperatures in the mid 80s, low relative humidity values, and dry vegetation will bring elevated conditions to the mountains and valleys in both Los Angeles and Ventura County. Gusty winds were expected to start around 10 PM PST Saturday and are expected to last through Monday afternoon. A red flag warning is issued when the weather conditions may indicate a period of weather that could lead to extreme burning conditions. During this time, it is important to heed local burn bans, properly discard any cigarettes, and avoid activities that cause open flames or sparks. With the dry vegetation, warm temperatures, gusty winds, and low humidity it doesn’t take much to spark a wildfire!
Santa Ana winds are most often characterized as being hot/dry winds which blow in from the desert towards the coast. These winds tend to occur during the following time frame (between September and May) when the desert is cooler than the Los Angeles basin. To learn more about fire weather and fire weather education, be sure to click here! © 2018 Meteorologist Shannon Scully  In a particularly calamitous year for natural disasters across the United States, wildfires continue to burn in California past the normal fire weather season. A new solution to arm fire weather officials, led by researchers at the University of Wyoming, hopes to model wildfire growth in an effort to close a 12-hour information gap provided by NASA's Active Fire dataset. While the Active Fire dataset (collected from the Moderate Resolution Imaging Spectroradiometer instrument on board NASA's Aqua and Terra satellites) provides a high-resolution snapshot of the burning wildfires, it suffers temporally. According to the researchers, the more readily available that updates about the wildfire's behavior or change in growth are, the more informed fire management officials can be when making critical decisions, such as mass evacuations. Researchers at the University of Wyoming developed a computer model to simulate fire growth and spread on the scale of minutes based on factors such as fuel moisture, land topography, and real-time weather. Preliminary results were shared with fellow scientists at the American Geophysical Union Fall Meeting in New Orleans last December. In the results, the model was compared to NASA's Visible Infrared Imaging Radiometer Satellite data in three different wildfires that occurred in Wyoming and Montana in 2017; while the model tended to over-predict the fire area, it did predict more than 86% of the actual burning area. According to scientists at the American Geophysical Union who attended the preliminary results session, the model looks incredibly promising. The researchers at the University of Wyoming plan to continue their investigations in an effort to improve their model by looking at the California wildfires in 2018. Check out the full press release from the AGU here, or read more about fire weather on our site here. © 2018 Meteorologist Chris Stubenrauch |
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